Small residential arch bridge design

[CCox]

I am looking at designing a small concrete arch bridge. The owner wants to do reinforced concrete. No precast; he wants it to look like the old European style bridges. The bridge will be for vehicular traffic. It will be approximately 20' wide by 45' long. Attached is a drawing showing the rough concept.

Does anyone have resources on designing a bridge of this type? Assistance would be greatly appreciated.

Thanks.

 

[SlideRuleEra]

Contech Bridges & Structures

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[oldestguy]

There has to be many references out there, This one may get you started. Do a Bing search, not Google.

https://www.bridgeweb.com/Stone-arch-bridges-make-a-comeback/4078

 

[oldestguy]

Here is another. Pretty complete.

https://scholars.unh.edu/cgi/viewco...com/&httpsredir=1&article=1032&context=honors

 

[IDS]

45 foot span isn't that small. Why no precast? Given that there are a number of suppliers of precast arches in that size range it seems the most sensible way to go.

Doug Jenkins
Interactive Design Services

http://newtonexcelbach.wordpress.com/

 

[WARose]

IIRC, AASHTO has a section that deals with it. There are a variety of resources out there.

As someone who has done some arches let me tell you: save yourself some headaches and (if possible) select a geometry that always has your cross-section in compression.

 

[CCox]

Thanks everyone for quick replies. I checked out the second website oldestguy recommended. You are right; very thorough discussion of it.

I also found some other resources online that give me some guidance. It can't be that difficult, right? I mean there are bridges like this thousands of years old still standing

IDS:
45' is the out-to-out length. The clear span of the inside arch is much smaller. That seems small to me, especially in comparison to the DOT bridges I analysed in college.
I'm not sure why the owner doesn't want to use precast. My first thought was to go precast as well. I have a phone conversation today with him and the contractor today, so I get to find out.

WARose:

Thanks for the tip. If I have any specific questions as I get into this, I'll bug you .


Thanks,

Cody

 

[JoelTXCive]

Our land department uses Contech bridges all the time.

Let the owner know you can clad the bridge in masonry, or do other surface treatments to get the look they are going for. We often have architects involved in our projects and the Contech people are usually pretty open to customizing the setup for a client.

 

[WARose]

I'd back what the others are saying as well (about using precast if you can). In the application you are talking about.....getting the veneer to hang on will be important. The precast guys have ready made details for that.

 

[SlideRuleEra]

I am looking at designing a small concrete arch bridge.
It will be approximately 20' wide by 45' long.
It can't be that difficult, right?

Wanna bet?
Also, get a good geotechnical report and ask the contractor is he has experience forming/placing heavy, complex concrete pours over water.

See "Concrete Arch Bridge Analysis" that ET member Bridgebuster provided.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[CCox]

Slide,

No bets, since I've never designed one. It was a lighthearted comment anyway. Thanks for the resource. It is very technical and what I am after.

 

[SlideRuleEra]

CC - I noticed the "" and knew you were kidding. If you have to use concrete, do talk to the contractor (soon) about his experience and capabilities... bridges are not buildings that just happen to be over water... I've built a few, one even had a very shallow arch profile - very difficult to form correctly. If the forming is not right, bridge will look terrible... don't ask how I know that.

For other references check Google Books. Since virtually any publications on concrete arch bridges will be decades old, you may be able to find and download complete books, free.

http://www.SlideRuleEra.net

http://www.VacuumTubeEra.net

 

[CCox]

Thanks Slide. I appreciate your insight. I'll try Google Books. Some of the references I found were decades old.

I'll mention to the owner and contractor using Contech pre cast bridges. They are pretty slick and serve for this exact purpose. It might be the case of putting the clients needs ahead of my wants. I really want to design this bridge because I enjoy out of the ordinary projects.

One thought I had for formwork was to use corrugated arched culvert pipe. I haven't looked into this closely though.